REPLICATION OF DNA

     DNA replication is the process by which a cell duplicates its DNA, ensuring that each new cell receives an identical copy of the genetic material. Here’s a concise overview of the process:

 Steps in DNA Replication:

  1. Initiation:

    • Origin of Replication: Replication begins at specific sites called origins of replication.
    • Unwinding: Enzymes called helicases unwind the DNA double helix, creating replication forks.

  2. Priming:

    • RNA Primase synthesizes short RNA primers complementary to the single-stranded DNA. These primers provide a starting point for DNA synthesis.

  3. Elongation:

    • DNA Polymerase adds nucleotides to the growing DNA strand, extending from the RNA primer. It synthesizes new DNA in the 5' to 3' direction.
    • The leading strand is synthesized continuously, while the lagging strand is synthesized in short segments called Okazaki fragments, which are later joined by DNA ligase.

  4. Termination:

    • Replication continues until the entire DNA molecule is copied. Specific termination sequences signal the end of replication.

  5. Proofreading and Repair:

    • DNA polymerases have proofreading abilities to correct errors during replication. Additional repair mechanisms also help maintain DNA integrity.

SIGNIFICANCE:

  • Semi-Conservative Process: Each new DNA molecule consists of one original strand and one newly synthesized strand.
  • Enzymes Involved: Helicase, RNA primase, DNA polymerase, and ligase are crucial for the process.
  • Speed and Fidelity: DNA replication is remarkably fast and accurate, with mechanisms in place to minimize errors.

This process is vital for cell division, growth, and maintenance of genetic information. 

DIAGRAM:



Comments

Post a Comment

Popular posts from this blog

Biochemistry plays in space exploration

  Biochemistry plays a critical role in space exploration by   helping to ensure the health and well-being of astronauts .   Space travel can have many negative effects on the human body, including: Bone and muscle loss Cardiovascular changes Weakened immune systems Hormonal imbalances Abnormal digestion and absorption Abnormal iron metabolism Ophthalmological issues   Biochemistry helps to develop strategies to counteract these effects. This includes:   Nutritional counter measures NASA's Nutritional & Biochemistry team develops and validates nutritional countermeasures to prevent or minimize the negative effects of spaceflight on the human body. For example, astronauts may need less iron during long-duration missions.   Understanding metabolic processes Understanding the impact of space travel on metabolic processes is vital for designing effective countermeasures.   Designing better equipment and technologies Understanding what happens...
Read more

Kidney function tests

Image
  Kidney function tests  Kidney function tests are essential for assessing how well your kidneys are working.  1. Blood Tests: Serum Creatinine : Measures the level of creatinine, a waste product from muscle metabolism. Elevated levels may indicate impaired kidney function. Blood Urea Nitrogen (BUN) : Measures the amount of nitrogen in your blood from urea, another waste product. High levels can suggest kidney issues. Estimated Glomerular Filtration Rate (eGFR) : Calculated using serum creatinine, age, sex, and race. It estimates how well your kidneys are filtering blood. An eGFR below 60 may indicate kidney disease. 2. Urine Tests: Urinalysis : A dipstick test that checks for protein, blood, glucose, and other substances. Presence of protein (proteinuria) can indicate kidney damage. 24-Hour Urine Collection : Measures the total amount of waste products excreted in urine over 24 hours. This can help assess kidney function and detect kidney stones. 3. Imaging Tests: U...
Read more

Mpox

Image
  Mpox(monkeypox) Mpox, previously known as monkeypox, is a viral illness caused by the monkeypox virus, a species of the genus  Orthopoxvirus . There are two distinct clades of the virus: clade I (with subclades Ia and Ib) and clade II (with subclades IIa and IIb). In 2022–2023 a global outbreak of mpox was caused by the clade IIb strain.  Mpox continues to be a threat today, and an upsurge of cases in the Democratic Republic of the Congo and other countries caused by clades Ia and Ib has raised concern. There are vaccines for mpox. Vaccination should be considered along with other public health interventions.  Common symptoms of mpox are a skin rash or mucosal lesions which can last 2–4 weeks accompanied by fever, headache, muscle aches, back pain, low energy and swollen lymph nodes.  Mpox can be transmitted through close contact with someone who has mpox, with contaminated materials, or with infected animals. During pregnancy, the virus may be passed to ...
Read more